The answer of course is to put on a slim case, but phones can still break with these. The other option is to use a bulky case, which can ruin the look of the phone.

Phillip Frenzel, an engineer at Aalen University in Germany, is not a fan of the bulky case so he designed the Active Dampening (AD) system, a slimmer case that has eight hidden springy legs that pop open when the phone is falling and cushion its landing.

The case has sensors that can detect when it’s in free fall and it’s quick enough to open them from pocket height.

In its popped-out state, four legs curl around the front of the phone, and four more curve backwards, protecting both sides and corners when the phone lands.

As seen in this video, closing the legs simply requires pressing each pair together and then folding them back into the case like a pocket knife.

The clever design won the student an award from the German Society for Mechatronics. Frenzel wanted to develop a kind of airbag for phones when his phone broke after a fall.

The case, dubbed ADCase, is currently a prototype, but according to Frenzel’s website, he’s planning to launch a crowdfunding campaign on Kickstarter soon.

The case also includes an extra battery that can charge the phone, wirelessly or by USB cable. The cover is 4.9mm (0.19in) thick, so it would make an iPhone X 12.6mm (0.5in) thick. The legs reach around the front to give it a three-centimeter, or 1.2in, buffer.

Frenzel and business partner Peter Mayer have developed AD cases for all iPhone models from the iPhone X to the iPhone 6 and 6 Plus.